What may be helpful to the wwvb projects is what is always fixed. This comes out of the NIST document. Assume you have a fairly good oscillator. If it can hold within 1/2 cycle of 60 KHz (10 us) for 47 seconds you can simply sample the top minute sync word. Thats from 59-11 seconds. Always fixed. But thats a bit too easy. NIST gave us a bit more of a challenge. At 10 and 40 past the hour the slow code runs and its format is different. But has a 106 second sync word thats always fixed and always at the same location. If you have a locked oscillator then the timecode recovery is reasonable. Decoding the actual timecode is a serious pain. Good luck Paul WB8TSL
On Fri, Jul 31, 2020 at 6:07 PM Poul-Henning Kamp <[email protected]> wrote: > -------- > Bob kb8tq writes: > > > It also *very* much depends on the stability of your local reference and > the > > stability of the ionosphere. Unless both are 'pretty darn good' a > hundred second > > integration is utter nonsense > > This is why Loran-C was so superior to any and all CW based modulations. > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > [email protected] | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by incompetence. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
